Previous answer is
Special feature :Yasumitsu was a son of the Osafune Shigeyoshi and worked with Morimitsu.
I think these sword makers were kept as the top ranking swordmakers
at early Muromachi period. The blade has very clear midare utsuri appear on the ji.
At early Muromachi period,it is quite surprised that wonderful texture was made.
This blade is very good condition without Kizu and flow.
Also on the shinogiji, we can see the texture of the Jigane.
Generally Yasumitsu and Morimitsu made Tachi a few but Tanto and small wakizashi mainly.
The blade is well known high ranking sword makers and alsso cut well sword(Oo wazamono cutting test ranking)
Morimitsu and Yasumitsu are well known sword smith in early Muromachi period at Bizen schoo.
Especialy Morimitsu is well known the most famous sword smith as fantastic Jigane.
This sword is typical Morimitsu and pretty nice quality of the blade.
Recently it is very difficult to obtain such kind of fantastic sword.
The blade is mentioned as Saijyo Oowaza mono(the top well cut sword ranking.)
Appraisal Quiz #320 (December 5th, 2014)
Who made this sword do you think ?
Hints. ※The picture will be enlarged
Blade length : 64.24cm or inches.
Sori : 1.35cm or inches.
Mekugi : 1
Width at the hamachi :3.12 cm or inches.
Width at the Kissaki : 2.49 cm or inches.
Kasane : 0.61 cm or inches.
Shape : The blade is wide and thick with small sori and long kissaki nice looking shape.
On the moot side, in the beautiful Koshibi,Sank tuck ken is engraved and on the back, Gomabashi and rendai is engraved.
Jitetsu :Itame had well grained with jinie attach beautiful excellent texture mixed
up Hollad iron and Japanese Tamahagane.
Hamon : Niedeki suguha based with a lot of ash soft feeling nice Habuchi.
Boshi is midarekomi style and turns back yakisage style.
there are some Muneyake on the Shinogiji.
Answer will be posted at next Appraisal Quiz.
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